Picture a tropical forest in your imagination. What comes to mind? Large, thick trees? Green foliage? A warm, wet climate? Millions of insects, plants, and animals? If you imagined this, you would not be far off. This abundance of life is known as biodiversity, all types of living organisms within a given area. In 1988, environmentalist Norman Myers set out to define the world’s most biodiverse areas in decline so they could be protected. He published a paper identifying 10 biodiversity hotspots with unique plant species and serious habitat loss. Comparatively, these places contain more species than 97.5 percent of the rest of Earth. In this paper, he outlined two criteria to qualify an area as a biodiversity hotspot:

• The region must have at least 1,500 vascular plant species found nowhere else on Earth (known as an endemic species). Vascular plants have tissues arranged in unique patterns and allow the plant to transport fluid. There are two different types of vascular tissues, called xylem and phloem.
• The region must have lost at least 70 percent of its original recorded surface area.

As of 2022, there are 36 official biodiversity hotspots around the world. Scientists have observed that although biodiversity hotspots are currently composed of approximately 2.5 percent of the land, they are home to nearly 43 percent of Earth’s known endemic mammals, reptiles, and bird species, as well as more than half of the world’s endemic plant species. Biodiversity hotspots are also home to around two billion humans, many of whom rely on healthy ecosystems for their survival and wellbeing. Although a few of these hotspots hold some of the highest human population densities on the planet, environmentalists suspect that much of human-environment impacts are due to human activities, such as reshaping natural habitats for farmland/large-scale food production or the over-exploitation of species through hunting and wildlife trade, as opposed to human population density.

This map layer was created by Conservation International, an investor in the Critical Ecosystem Partnership Fund (CEPF), and visualizes the 36 official biodiversity hotspots.

In 1989, Conservation International adopted Myers’ hotspot criteria and in 1996, they reassessed Myers’ hotspots, as well as examined new areas they believed he overlooked. After a three-year review, Conservation International designated 25 biodiversity hotspots globally. By 2005, this number rose to 34, based on analyses from nearly 400 specialists. An additional two biodiversity hotspots have been identified since 2010. The first was in 2011, when researchers from the Commonwealth Scientific and Industrial Research Organization (CSIRO), identified the Forests of East Australia to be the 35th biodiversity hotspot. Then in February of 2016, the North American Coastal Plain was recognized as Earth’s 36th biodiversity hotspot.

The Critical Ecosystem Partnership Fund works to support the development of conservation strategies by building long-term local conservation leadership and nurturing sustainable development in order to protect biodiversity hotspots. Since 2000, CEPF has granted over 271 million U.S. dollars to over 2,500 civil society organizations and individuals. They have also worked to conserve more than 900 species on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species, and have improved the management and protection of 50.3 million hectares (~124 million acres) of key biodiversity areas.